Air pre-cooler method and apparatus

Abstract

An apparatus and method for cooling, air which apparatus includes an indirect evaporative cooler, a direct-contact ice-water chiller, a reheat coil component, an ice-thermal-storage component and an ice-manufacturing refrigeration chiller to provide alternative air-flow paths and alternative component combinations. The method provides alternative fluid-flow paths through electable combinations of the several components to effect the desired lowering of air temperature, relative humidity and air density in the cooled air.

What is claimed is: 
     
       1. A precooling system for combustion air communicated to a gas turbine, said system operable to receive ambient air at a wet bulb and dry bulb temperature, an ambient relative humidity and an ambient air density, and to provide said combustion air at a second temperature lower than ambient temperature and a second density greater than ambient density, said system comprising: a direct-contact-air-chiller having a fluid-to-air exchange chilling media, ana ri inlet side, an air outlet side, a fluid inlet, a cooling fluid at a first temperature, and a sump for recovery of coolant fluid passing through said media from said fluid inlet passage, said direct-contact-air-chiller operable to receive air at an ambient temperature and density for reduction of said ambient air temperature and absolute humidity, and to increase said air density for communication to said gas turbine;   means for reducing said cooling fluid temperature below said ambient wet-bulb temperature, which reduced-temperature fluid in said direct-contact-air-chiller is operable to reduce said ambient air temperature below said ambient wet-bulb temperature and to reduce said air absolute humidity;   a pump,   a first conduit connected between said pump and said fluid inlet for communication of said coolant fluid to said fluid-temperature-reducing means, which coolant fluid passes through said chilling media to cool said ambient air communicating through said chilling media from said inlet side for discharge from said outlet side;   a first valve coupled to said sump and said fluid-temperature-reducing means, said first valve having a first servomechanism,   a second conduit connected between said first valve and said fluid-temperature-reducing means;   a second valve having a second servomechanism and coupled to said pump, said first valve and said fluid-temperature-reducing means,   said first valve operable by said first servomechanism to communicate fluid from said sump to any of said second valve and said fluid-temperature reducing means, which second valve is operable by said second servomechanism to communicate said coolant fluid from any of said first valve and said fluid-temperature-reducing means to said pump for recirculating coolant fluid at a predetermined fluid temperature to said direct contact chiller for treating said ambient air.   
     
     
       2. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said cooling fluid is water. 
     
     
       3. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said chilling media is a cross-flow arrangement. 
     
     
       4. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said chilling media is a counterflow arrangement. 
     
     
       5. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said chilling media is a parallel flow arrangement. 
     
     
       6. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said predetermined air temperature is about 44 degrees Fahrenheit. 
     
     
       7. A precooling system for gas-turbine combustion air as claimed in claim 1, wherein said means for reducing said fluid temperature is a thermal storage system having an ice making plant and a thermal storage unit defining a chamber for retention of coolant fluid and ice, means for refrigerating positioned in said thermal storage unit and operable to produce said ice, said refrigerating means coupled to said ice making plant;   said second conduit connecting and providing fluid communication from said first valve and sump to said chamber to contact said cooling fluid with said ice for cooling-fluid temperature reduction for recirculation to said fluid inlet.   
     
     
       8. A precooling system for gas-turbine combustion air as claimed in claim 7 further comprising means for sensing said fluid temperature and operable to provide a signal; a line connecting said sensing means and at least one of said first valve servomechanism, said second valve servomechanism and said pump, which at least one element is responsive to said signal to control cooling fluid flow and communication through said first valve to said chamber and second valve.   
     
     
       9. A precooling system for gas-turbine combustion air as claimed in claim 7 further comprising means for sensing one of said combustion air temperature and relative humidity and operable to provide a signal, a line connecting said means for sensing and at least one of said first and second valve servomechanisms, which servomechanisms are responsive to said signal to control said cooling-fluid flow through said first and second valves to control said one sensed combustion air parameter.   
     
     
       10. A precooling system for gas-turbine combustion air as claimed in claim 9 further comprising a reheating coil downstream of said direct contact chiller; means for heating said reheating coil to elevate said combustion air temperature to about said predetermined temperature and reduce the relative humidity.   
     
     
       11. A precooling system for gas-turbine combustion air as claimed in claim 10 further comprising an indirect evaporative cooler to reduce said ambient air temperature of said inlet air upstream of said direct-contact-chiller apparatus. 
     
     
       12. A precooling system for combustion air communicated to a gas turbine as claimed in claim 7 wherein said means for refrigerating is a cooling coil positioned in said chamber and having a refrigerant therein; said ice-making plant having an evaporator, a condenser, an expansion device and a compressor coupled to said cooling coil, said ice-making plant operable with said coil and refrigerant to cool and freeze said cooling fluid in said chamber.   
     
     
       13. A precooling system for combustion air communicated to a gas turbine, said system operable to receive ambient air at a wet bulb and dry bulb temperature, an ambient relative humidity and an ambient air density, and to provide said combustion air at a second temperature lower-than-ambient air temperature and greater-than-ambient air density, said system comprising: a direct-contact-chiller with a fluid inlet, a sump and a first fluid for cooling,   said direct-contact-chiller operable to receive air and reduce the air temperature;   means for reducing said first-coolant-fluid temperature below said ambient-air, wet-bulb temperature, which cooled fluid is operable to reduce said air temperature below said air wet-bulb temperature and to reduce the air absolute humidity;   first means for recirculating said first coolant fluid from said sump to said direct-contact-chiller fluid inlet;   means for coupling said first recirculating means and said fluid-temperature-reducing means to communicate spent first cooling fluid form said sump and, to channel and control the rate of cooling fluid flow to said recirculating means and said fluid-temperature-reducing means to provide cooling fluid at said fluid inlet at a predetermined fluid temperature for said direct-contact-chiller;   an indirect-evaporative-cooler with a second fluid for cooling,   said indirect evaporative cooler having a tubular coil with a fluid passage, an entry end and an exit end,   at least one fin mounted on said tubular coil to enhance air contact and heat transfer.   a cooling tower for said second cooling fluid, which has a second fluid inlet passage and a second sump;   second means for recirculating said second cooling fluid coupled between said cooling-tower sump and said cooling-tower second fluid inlet passage,   said tubular coil serially positioned between said second means for recirculating and said cooling-tower second fluid inlet passage for recirculating said second coolant fluid through said coil;   said indirect evaporative cooler operable to receive said ambient air and pass it past said coil for reduction of said ambient air temperature, maintenance of said air absolute humidity and communication of said air to one of said direct-contact-chiller and said gas turbine.   
     
     
       14. A precooling system for gas-turbine combustion air as claimed in claim 13 wherein said direct-contact chiller and said cooling tower are cross-flow arrangements. 
     
     
       15. A precooling system for gas-turbine combustion air as claimed in claim 13 wherein said direct-contact chiller and said cooling tower are counterflow arrangements. 
     
     
       16. A precooling system for gas-turbine combustion air as claimed in claim 13 wherein said direct-contact chiller and said cooling tower are parallel flow arrangements. 
     
     
       17. A precooling system for gas-turbine combustion air as claimed in claim 13 wherein said first means for recirculating has a conduit communicating between said first sump and said direct-contact chiller fluid inlet passage, and a pump positioned in said conduit to recirculate said first cooling fluid from said sump to said direct-contact-chiller fluid inlet passage. 
     
     
       18. A precooling system for gas-turbine combustion air as claimed in claim 17 further comprising a second conduit and a second pump mounted in said second conduit; said second pump operable to recirculate said second cooling fluid through said second conduit, finned coil and said cooling tower.   
     
     
       19. A precooling system for gas-turbine combustion air as claimed in claim 18 further comprising first means for sensing one of said temperature and relative humidity of said air to said gas-turbine, which sensing means provides a signal; said first sensing means coupled to said second pump to communicate said sensed signal, which second pump is actuable to circulate said second coolant through said tubular coil. 
     
     
       20. A precooling system for gas-turbine combustion air as claimed in claim 18 further comprising a reheating coil downstream of said direct contact chiller and indirect evaporative cooler, said reheating coil having a fluid passage with an inlet end and an exit end; means for coupling positioned in said second conduit and connected to said reheating coil inlet end,   said reheating coil exit end connected to said second conduit downstream of said coupling means;   said coupling means operable to receive said second cooling fluid downstream of said indirect-evaporative tubular finned coil and to communicate a second cooling fluid to said second conduit and, to said reheating coil to slightly reheat said combustion air to a predetermined temperature, to reduce the relative humidity, while holding contact absolute humidity.   
     
     
       21. A precooling system for gas-turbine combustion air as claimed in claim 20 further comprising second means for sensing one of said combustion air temperature and relative humidity to provide a sensed signal; said means for coupling a two-way valve with a servomechanism connected to said second sensing means, said servomechanism operable to couple said valve, said second conduit and said reheating coil in response to said second signal to control said combustion air temperature and relative humidity.   
     
     
       22. A precooling system for gas-turbine combustion air as claimed in claim 18 and further comprising a motor drive fan to accelerate said air flow through said system to said gas turbine. 
     
     
       23. A method for providing reduced-temperature air to a gas-turbine at a temperature less than air cooled by a fluid at about ambient air temperature, said reduced-temperature air is at a density greater than ambient air density, said reduced-temperature air provided through a system having a direct-contact air chiller with a sump, a fluid inlet and a cooling fluid recirculable through said direct-contact-chiller to cool air passing therethrough, means for recirculating said fluid between said sump and said inlet, and means for coupling said sump and recirculating means, said method comprising: a. providing an ice-chiller apparatus with a thermal storage unit for receiving and reducing the temperature of said cooling fluid;   b. connecting said sump and said thermal storage unit with said coupling means for communication of said fluid to said thermal storage unit;   c. communicating said cooling fluid from said sump to said thermal storage unit for reducing the temperature of said cooling fluid below said ambient-air temperature;   d. coupling said thermal storage unit to said recirculating means to communicate said reduced-temperature fluid to said inlet and cooler;   e. providing an indirect-evaporative-cooler operable to receive said ambient air and reduce the temperature of said ambient air to a second temperature less than said ambient-air temperature;   f. channeling said ambient air through said indirect-evaporative-cooler for communication to one of said gas turbine and said direct-contact-chiller; and,   g. reducing the temperature of said air at said second temperature in said direct-contact-chiller to provide said reduced-temperature air to said gas turbine at a third temperature less than said second temperature and said first-reduced temperature.   
     
     
       24. The method for providing reduced-temperature as claimed in claim 20 and further comprising: a. providing means for reheating said reduced-temperature air to said gas turbine;   b. communicating said air from said direct-contact-chiller and said indirect-evaporative-cooler through said reheating means; and,   c. elevating the temperature of said air passing through said reheating means to a predetermined fourth temperature at a relative humidity less than a predetermined relative humidity for transfer to said gas turbine.   
     
     
       25. A air precooling system operable to receive ambient air at a wet bulb and dry bulb temperature, an ambient air relative humidity and an ambient air density and to discharge air at a predetermined lower than ambient temperature and greater than ambient air density, said system comprising: a direct-contact-air chiller with a first fluid for cooling, a fluid inlet and a fluid sump;   an indirect evaporative cooler with a second fluid for cooling;   means for reducing said first cooling fluid temperature below said ambient air wet-bulb temperature;   first means for recirculating said first cooling fluid;   first means for coupling said sump to said cooling fluid-temperature reducing means and said first recirculating means to said direct evaporative cooler, said first means for recirculating operable to transfer said first cooling fluid from said fluid sump to said fluid inlet from each of said direct contact chiller fluid sump and said fluid temperature reducing means;   second means for recirculating said second cooling fluid through said indirect evaporative cooler;   a first cooling tower coupled downstream of said indirect evaporative cooler and upstream of said second recirculating means, said cooling tower operable to receive said second cooling fluid;   means for reheating said discharged air, which reheating means has a reheating-means inlet port and a discharge port;   second means for coupling said second recirculating means and said reheating means at said reheating-means inlet port downstream from said indirect evaporative cooler, which reheating means is coupled to said second recirculating means at said discharge port downstream of said second coupling means, said reheating means operable to warm said discharge air to about said predetermined temperature and reduce the relative humidity at a constant absolute humidity.   
     
     
       26. An air precooling system as claimed in claim 25 wherein said means for reducing said first cooling fluid temperature has an ice-making plant utilizing a refrigerant for freezing, said system further comprising a second cooling tower coupled to and operable with said ice-making plant.   
     
     
       27. A precooling system for combustion air communicated to a gas turbine, said system operable to receive ambient air at a wet bulb and dry bulb temperature, an ambient air relative humidity and an ambient air density and to provide said combustion air at a predetermined lower than ambient temperature and a greater than ambient air density, said system comprising: a direct-contact-air chiller with a first fluid for cooling, media for cooling, an air inlet side, an air outlet side, a fluid inlet and a fluid sump for recovery of said first cooling fluid flowing through said media;   an indirect evaporative cooler with a second fluid for cooling;   means for reducing said first cooling fluid temperature below said ambient air wet-bulb temperature;   first means for recirculating said first coolant fluid, said recirculating means having a first pump and a first conduit between said first pump and said direct-contact-air chiller fluid inlet;   first means for coupling said sump with said first recirculating means and said fluid temperature reducing means for communication of said first cooling fluid to said fluid-temperature-reducing means and said first recirculating means;   said first recirculating means connected to said direct-contact-air chiller fluid inlet for communication of said first cooling fluid from said sump and said fluid-temperature-reduction means to said fluid inlet and said media to cool said ambient air passing from said air inlet side to said air outlet side;   said first coupling means having a first valve, a second valve and a second conduit connecting said first valve and said fluid temperature reducing means,   said first valve having a first servomechanism, said first valve coupled to said sump and said second valve, which first valve is operable to said first servomechanism to communicate first cooling fluid from said sump to said second valve and said fluid-temperature-reducing means,   said second valve having a second servomechanism, said second valve coupled to said first pump and said fluid-temperature-reducing means, said second servomechanism operable to actuate said second valve to communicate said first cooling fluid from said first valve and from said fluid-temperature-reducing means to said first pump for recirculation of said direct-contact-air chiller fluid inlet;   second means for recirculating said second cooling fluid through said indirect evaporative cooler;   means for reheating said discharged air, which reheating means has a reheating-means inlet port and a discharge port;   second means for coupling said second recirculating means and said reheating means at said reheating-means inlet port downstream from said indirect evaporative cooler, which reheating means is coupled to said second recirculating means at said discharge port downstream of said second coupling means, said reheating means operable to warm said discharge air to about said predetermined temperature and reduce the relative humidity at a constant absolute humidity.   
     
     
       28. A precooling system for gas-turbine combustion air as claimed in claim 27 wherein said media for cooling is provided in a crossflow arrangement. 
     
     
       29. A precooling system for gas-turbine combustion air as claimed in claim 27, wherein said media for cooling is provided in a counterflow arrangement. 
     
     
       30. A precooling system for gas-turbine combustion air as claimed in claim 27, wherein said media for cooling is provided in a parallel flow arrangement. 
     
     
       31. A precooling system for gas-turbine combustion air as claimed in claim 27 wherein said predetermined discharge air temperature is about 44 degrees Fahrenheit. 
     
     
       32. A precooling system for gas-turbine combustion air as claimed in claim 27, wherein said predetermined discharge relative humidity is less than 85 percent. 
     
     
       33. A precooling system for gas-turbine combustion air as claimed in claim 27, wherein said indirect evaporative cooler has a cooling tower with a second sump and a tower fluid inlet passage, a tubular coil having a through-bore, an input end, an exit end and at least one fin mounted on said tubular coil for enhanced heat transfer;   said second means for recirculating having a second pump and a third conduit, said second pump coupled between said tower sump and tubular coil input end;   said second means for coupling is a third valve with a third servomechanism, said third valve coupled to said tubular coil exit end, said reheating coil input port and said third conduit, which third conduit is coupled to recycle said second fluid to said tower inlet passage downstream of said third valve;   said reheating coil exit end coupled to said third conduit for fluid transfer to said tower inlet passage;   said third valve operable by said third servomechanism to couple said third conduit and reheat coil for second fluid communication downstream of said tubular coil for recirculation to said tower.   
     
     
       34. A precooling system for gas-turbine combustion air as claimed in claim 33, wherein said reheating coil has a tubular member with a through passage and at least one heat-exchanging fin mounted on said tubular member to enhance heat transfer between combustion air and said tubular member, said reheating coil arranged upstream of said gas turbine and downstream of said direct and indirect evaporative coolers and electively engageable to reheat said combustion air to elevate said air temperature and reduce said inlet air relative humidity at constant absolute humidity.   
     
     
       35. A precooling system for gas-turbine combustion air as claimed in claim 34 further comprising at least one means for sensing said combustion air temperature and coupled to at least one of said first valve, second valve and third valve servomechanisms to control said at least one valve and cooling fluid communication therethrough. 
     
     
       36. A precooling system for gas-turbine combustion air as claimed in claim 35 further comprising a fan for accelerating said air through said system to said gas turbine.